【摘要】 在青岛和海南进行40CrNi2Si2MoVA超高强度钢的大气暴露实验,对暴露后的材料性能以及腐蚀形貌进行了研究。结果表明,40CrNi2Si2MoVA钢在海洋性大气环境中,腐蚀以均匀腐蚀为主,随环境不同和腐蚀发展的变化,腐蚀产物成分和结构不同,主要成分是Fe3O4,Fe2O3,γ-FeOOH和α-FeOOH。腐蚀失重与时间的关系可用幂函数w=atb(b<1)回归。40CrNi2Si2MoVA钢在海洋性大气环境下具有较高的应力腐蚀敏感性,应力腐蚀为沿晶开裂模式,裂纹起源于表面产生腐蚀的部位,并向内部扩展。40CrNi2Si2MoVA钢在海南万宁的腐蚀速率以及应力腐蚀敏感性明显高于在青岛团岛的。由于环境腐蚀对材料的影响,导致其抗拉强度的损失,从而使其抗应力能力降低,在更低的强度水平和更短的时间内产生断裂。更多还原

【Abstract】 Outdoor exposure tests in marine atmosphere of 40CrNi2Si2 MoVA high strength steel were carried out in Qingdao(on the east coast of Shandong facing the East China Sea) and Wanning(on the east coast of Hainan Island facing the South China Sea) respectively.The test samples include plate sample,samples for tensile and various stress corrosion cracking(SCC) test.The corrosion behavior of the steel was examined by means of mass loss measurement,SEM,as well as the change of mechanical property and SCC susceptibility.The results show that general corrosion occurs on the surface of 40CrNi2Si2 MoVA steel,corrosion products are mainly Fe3O4、Fe2O3、γ-FeOOH and α-FeOOH;the mass losses vary at w=atb(b<1).The steel exhibited high SCC sensitivity in marine environment with typical intergranular cracking,and the crack initiated from corrosion pits in the surface and developed inwards.Higher corrosion rate and higher SCC sensitivity were observed in Hainan rather than in Qingdao.The decrease of tensile strength is result from corrosion inducing premature fracture in a short term.更多还原